Documentation

This type-class supports parallel composition of processes. You may use
the runParallel function to run a list of processes, or the <||> operator
to run just a pair of processes.

In each case, the composition waits for all processes to finish, either
successfully or with poison. At the end of this, if any process
exited with poison, the composition will "rethrow" this poison. If all
the processes completed successfully, the results will be returned. If
you want to ignore poison from the sub-processes, use an empty poison
handler and onPoisonTrap with each branch.

Runs the given list of processes in parallel, and then returns a list
of the results, in the same order as the processes given. Will only return
when all the inner processes have completed.

In version 1.5.0, a bug was introduced such that runParallel [] would deadlock;
this was fixed in version 1.5.1.

Executes a forking block. Processes may be forked off inside (using the
fork function). When the block completes, it waits for all the forked
off processes to complete before returning the output, as long as none of
the processes terminated with uncaught poison. If they did, the poison
is propagated (rethrown).

Forks off the given process. The process then runs in parallel with this
code, until the end of the forking block, when all forked-off processes
are waited for. At that point, once all of the processes have finished,
if any of them threw poison it is propagated.